1. Technical Field
The present invention relates generally to a semiconductor integrated circuit, and more particularly, to a semiconductor memory apparatus which controls a voltage skew and a method for controlling the same.
2. Related Art
In general, a memory apparatus such as a NAND flash memory uses various levels of voltage.
A flash memory may receive a high voltage and a low voltage. The high voltage may include a word line program voltage, a pass bias voltage, a low-level high voltage and so on. Here, the pass bias voltage is a voltage which is applied to word lines adjacent to a selected word line, and the low-level high voltage is a voltage which is applied to word lines spaced a predetermined distance or more from the selected word line.
Nonvolatile memory design engineers set such various voltages to a target level and properly use the voltages in an internal circuit.
However, the target level of such voltages may be influenced according to a process variation, a process skew, a geometrical effect, and the physical position of a chip. Therefore, a constant target voltage is requested despite such environmental effects.